In the case of known rotary atomizers of this kind, as shown in prior art references German OS 30 01 209 and German OS 31 29 075, which are used for coating motor-vehicle bodies among other things, the turbine-housing and the connecting supply and exhaust conduit elements thereof are subject to considerable temperature drop by the expanding process of the air-turbine, especially in the case of an efficient turbine unit operating at high rpm. The frequently warm and moist ambient air in the spray-booth can therefore lead to the formation of condensate upon the surfaces of the turbine-housing and also upon the conduit elements connected thereto. This is highly undesirable, mainly because the dripping condensation-water may reach the paint being sprayed, thereby spoiling the integrity of the paint coating.
In order to counteract the formation of the condensate, the prior art has taught to heat the air driving the turbine, but this is inadequate as it requires a considerable amount of power. The prior art has also taught to provide a large plastic or metal cover about the whole atomizer housing, but this is deficient in that it would lead to structural and rheological problems. Moreover the exterior surface of the cover, above all, would be subject to condensate formation.